Shiver Me Timbers: Daylighting for Timber Rattlesnakes in Vermont

It’s been an agonizingly slow thaw here in the state of Vermont, but spring is finally here! After a long winter, the ice is melting and we are preparing for the emergence period of our Timber Rattlesnakes. In northern areas like Vermont, rattlesnakes hibernate during our long, harsh winter. These overwintering sites (hibernacula) tend to be located in areas that warm up faster than others. This is largely attributed to two very important factors: the first being that they are predominantly found on southwest-facing slopes, providing favorable exposure and allowing maximum solar gain during the day. The second factor is that these slopes are covered in talus-like rock, which are excellent conductors of solar energy that soak up heat throughout the day, and remain warm long after sunset. These rocky sites surrounding the overwintering areas are vital for these rattlesnakes to reach optimum body temperatures as they emerge from their winter hibernation, giving them the energetic boost they need to begin their summer journeys.

Over time, surrounding forests encroach on these warm basking sites, stealing the much-needed sunlight these snakes require. The Orianne Society staff, along with the assistance of Vermont Fish & Wildlife and The Nature Conservancy (TNC) identified a few critical basking sites that were in need of “daylighting.”

With the necessary tools in hand, (Project Leader) Doug Blodgett and I hiked through the forest and scrambled up rock faces to reach the identified basking sites. Some of the competing vegetation is small enough that we can use handsaws and clippers, while larger specimens require chainsaws to be cut or girdled. We tried to identify trees that were casting shade onto the basking rocks, leaving the surrounding trees unharmed. The branches and stumps of the downed trees are collected in bundles and left in brush piles, providing the snakes with favorable habitat to harbor rodent prey, along with additional escape cover to hide under and protect themselves from predators.

In the days following daylighting, many snakes have been observed basking in the sun on these very rocks. This shows our efforts have been a success, allowing the Timber Rattlesnakes of Vermont the opportunity to kick start their summer journey. Subsequent use of the daylighted areas by basking rattlesnakes provided the final proof to us that our planning and clearing efforts had been successful.